Wire feeding mechanism



mg. 30, 1949. H. A. IMHOF 2,480,138

WIRE FEEDING MECHANISM Filed Aug. 8, 1946 Patented Aug. 30, 1949 WIRE FEEDING MECHANISM Herman A. Imhof, Beverly, Mass, assignor to United Shoe Machinery Corporation, Flemington, N. J a corporation of New Jersey Application August 8, 1946, Serial No. 689,175

Claims. 1

This invention relates to wire feeding mechanisms and is herein illustrated as applied to a fastening inserting machine of the type disclosed in Letters Patent of the United States No. 2,418,140, granted on April 1, 1947, in the names of Charles A. Robinson and Herman A. Imhof. It is understood, however, that the invention is limited neither in scope nor in utility to machines of the type above identified nor, indeed, to fastening inserting machines in general.

Machines in which a continuous strand of wire or similar material is used or processed, such as stapling machines provided with staple forming mechanisms, commonly have a wire feeding mechanism adapted to advance the wire strand from its supply (usually a rotatable reel on which the wire is wound up) through the machine to the wire processing station, e. g. the wire severing and fastening forming mechanism. It is essential in machines of this type that, each time a new reel is mounted in the machine, the wire be so threaded into the machine and through the various wire guiding and wire handling mechanisms that the leading end portion of the wire is fully advanced to its final position in which it is cated in proper relation to the wire processing mechanism before the machine operation is resumed. However, this is frequently difficult to accomplish, particularly if the wire, as is usual, follows a tortuous course in the machine and if the final position of the leading end portion of the wire cannot be readily observed by the operator. When threading-in a new wire strand, the operator manually advances the wire strand through the wire guiding and wire handling devices of the machine until the wire resists any further advancing movement, the operator then assuming that the leading end portion of the wire has reached its proper final position in the machine. Frequently, however, this is not the case, particularly if the front end of the wire strand is somewhat burred and, as a result, becomes lodged in a restricted wire guiding passage. Needless to say this results in a faulty operation of the machine. In fact, taking the case of the above mentioned fastening inserting machine, an incompletely threaded-in wire strand often will result in an improperly formed or incomplete staple, sometimes comprising only one leg. The improperly formed or incomplete staple will become crippled and lodged in the staple inserting mechanism during the operation of the latter and thus constitute a source of trouble, sometimes even leading to the breakage of machine parts.

It is therefore an object of the invention to provide an improved wire feeding mechanism adapted for use not only in intermittently advancing the wire strand during the machine operation but also in threading-in a new wire strand in such a. way that the wire strand is properly passed through the various wire guiding and wire handling devices of the machine and its leading end portion located in its proper final position in the machine.

The illustrated wire feeding mechanism comprises a wire feeding member (usually a roll) and a cooperating presser member (also usually a roll) which either is in position to hold the wire clamped against thefeeding member during the Wire feeding operation or is backed off to interrupt the feeding of the wire. For the purpose in view and in accordance with one feature of the invention, there is provided a movable wire stop controlled by the movement and the position of the pressure member, the construction and arrangement of the parts being such that, when the presser member is backed off and the wire feedis interrupted, the stop is located in its wire stopping position below the bite of the rolls, the stop being moved out of its wire stopping position in response'to movement of the presser member into position to hold the wire clamped against the feeding member. When a new strand of wire is to be threaded through the machine, the presser member is backed off and the wire stop moved into position to engage the leading end of the wire after it has passed between the presser member and the wire feeding member. The operative position of the wire stop is predetermined particularly with relation to the proper final position of the front end of the wire in the machine. As measured along the path of movement of the wire, the distance between the wire stop and the final position of the front end of the wire is a multiple of one feed increment. In the illustrated example, this distance is six times one feed increment. Thus, after the newly threaded-in wire strand has been arrested by the wirestop, the presser member is moved back into clamping position with relation to the feeding member thereby moving the wire stop out of the path of movement of the wire strand. By now running the fastening inserting machine idly through six cycles six feed' increments are imparted to the wire strand under the power operation of the machine, thereby insuring that the wire is properly threaded through the machine and that its front end is finally located in its proper position in the machine.

These and other features of th invention will now be described in detail with reference to the accompanying drawings and will be pointed out in the appended claims.

In the drawings,

Fig. 1 is a view in front elevation, partly in section, of a wire feeding mechanism in which the present invention is embodied, and showing also part of the fastening forming and inserting mechanism of 'a machine with which the wire feeding mechanism is associated;

Fig. 2 is a plan view of the wire feeding mechanism;

Fig. 3 is a view in front elevation of part ofthe wire feeding mechanism, showing the essential elements of the mechanism ina position of adjustment different from that shown in Fig. 1; and

Fig. 4 is a detail view of a hand lever by which the operation of the Wire feeding mechanism may be controlled.

As previously pointed "out the illustrated wire feeding and wire threading mechanism is shown as applied to a fastening insertin'g machine of the type disclosed in the above identified patent. As more fully described 'ther'e'in, th fastening inserting machine is designed to forn'rsta 'iles from a continuous strand bf staple wire and successive- 1y to insert the staples, thus formed, into a workpiece. The machine has a threat member H] which is movable toward and from the workpiece presented to the machine. The throat member carries a nozzle l2 having'provided in it 'a recess I4 into and through which the forward end portion of the wire strand iv-is fed to he severed from the strand by a knife "I6. There is provided an inside former [8 about which the severed end portion of the 'wires'trand is bent by the nozzle I2 during its movement toward the work to form a staple and there is furthermore provided a filler piece 20 which, after the-fermation of the staple, descends to fill the recess and toguide the staple during the operative stroke of a driver (not shown). 'The staple wire w is guided into the staple forming and driving 'meehanism by "a wire intake member 22 mounted in the machine frame. Th inner end of the "member '22 tooperates with the knife IB in shear-like fashion to sever the wire during the movement of the throat member and nozzle 12 toward the work. Extending partway into the wire 'iritake member is a wire conduit 24 in the forin of a closely wound coil spring which, before re'aches the wire intake member22, pa'sses through an adj us'table wire straightener 26 "of convention'al design.

The principal elementsof the wire feeding and wire threading mechanism areawire feedingroll 30'having in its periphery a wire'guidinggroove, and a pressure roll 32 which is spring-biased to force the wire w'passi'ng between the rolls 3!! and 32 into the groove in the "periphery 'o'f the wire feeding roll 39. As will be'describedmore in detail, both rolls 3!] and 32 are mounted in'a bracket '34 secured to the frame of "thefa'steninginserting machine. The above mentionedwirestraightener 26 also is secured tothe'bracket 3 4 'for adjust'me'nt heightwise of the machine. Rotatablymounted in the bracket 34 is a 'hori-zontal-shaft36about' the axis of which the wire feeding r011 301's freely rotatable. The wire "feeding roii'fifiis mounted for rotation on a fixed'bearing sleeve 31 (Fig. 2)surrounding the shaft '36 'and integral with-the T011 30 is a ratchet wheel 38 which is adapted to be rotated intermittently in the same'direction 'by a pawl 40 (-Fig. 3) pivotally secured-to an arm 42. The arm 42 has a split hub whichis -clampedon the forward end 'of the shaft -36 'by' a screw '44.

A spring 46 is extended between a pin in the for- Ward end of the shaft 36 and another pin carried by the pawl 40, and serves to hold the pawl against the ratchet wheel 38. The shaft 36 is rocked or rotated in opposite directions in time relation to the operation of the fastening forming and inserting mechanism to bring about an interr'nit'tent wire feeding movement of the roll 30. To't'his end the shaft 36 carries at its rear portion a pinion 48 which meshes with a rack bar 56 formed on a rod 52. As fully described in United States Letters Patent 1,854,204, granted on April 19, 1932, on an application filed in the name of Robert H. Lawson, and disclosing a fastening inserting machine of the above identified type, the rod 52 is reciprocated heightwise of the machine in time relation to the operation of the machine to rock the shaft 36. Rotation of the shaft 36 in a clockwise direction, as viewed in Figs. 1 and 3, causes the pawl 43, While in engagement with a tooth of the ratchet wheel 38, to impart a rotation to the wire feeding roll 36 to advance the wire one feed increment provided the pressure roll 32 is holding the wire strand w clamped against the wire feedingroll 36. Rotation of the shaft 36 in a counterclockwise direction, as viewed in Figs. 1 and 3, causes thepawl '43 to ride idly over the teeth of the ratchet wheel 38 preparatory to a reversal of the'shaft 3% during which another feeding movement is impartedto the wire feeding roll 30.

The pressure roll 32 is rota'tably mounted on the freely extending, smooth shank of a screw bolt 54 secured in thefront end of a horizontal supporting lever 56. The supporting lever 56 is mounted for pivotal movement about a pivot pin '58 between two spaced horizontal arms or flanges 60, 62 provided on the bracket 34. The rear end portion of the supporting lever 56 is engaged by one end of a spring '64 the other end of which 'is seated in a recess provided in the bracket 34. The spring64 tends to rotate the lever 56 about the pin 58 in a clockwise direction,

as viewed in Fig. 2, to cause the pressure roll 32 to clam-p the wire against the feeding roll 30.

As stated, in the normal operation of the ma-' be threaded through the Wire feeding mechanism,-

including the rolls 30 and 32, there is provided a hand lever 66 having a round hub 68 and mounted for rotation on the 'boltfifi adjacent tov the pressure roll 32. As illustrated best in 4, the hub 68 of the hand lever 66 has a flat portion Hi. The hub "68, including the flat portion 10. is adapted to cooperate with. a fixed abutment 12 provided on the bracket 34. If the hand lever 66 is so rotated about the bolt -54 that the fiat portion 10 of its hub 68 engages the abutment lzfthespring 54 is free to force the pressure roll 32 against the wire feeding roll 30 by-imparting-a slight rotation to the supporting lever '56 in a clockwise direction, as viewed in Fig. 2. Movement of the hand lever'66 into adifferent position of adjustmentin which the round portion of its hub 68 engages the abutment 12 forces the pressure roll 32 away from the feeding r011 30 by imparting a slightrotation to the supporting lever 56 in 'acounte'rclockwis'e direction, as viewed in Fig-z thereby compressing the spring 64. *In

the latter position of adjustment of the hand lever 56 the wire feeding mechanism is inoperative. V

To cause the wire strand w to enter properly between the two rolls 3i] and 32, there is provided a wire guiding member 14 secured to the bracket 34 and located above the bite of the rolls 3!] and 32. Located below the bite of the rolls 30 and 32 and also secured to the bracket 34 is a wire receiving member 16 into which the wire is fed by the feeding roll 30 in cooperation with the pressure roll 32. The upper extremity of the above mentioned Wire conduit 24 extends into the wire receiving member 16. The conduit 24 is surrounded between the member 16 and the wire straightener 26 by a metal tube 18. It is the purpose of the tube 18 to prevent the wire strand from distorting the wire conduit 24 when the strand is being threaded into the fastening forming mechanism and its front end has become lodged in the wire conduit or in the fastening forming mechanism by reason of its meeting some obstruction therein or by reason of the formation of a burr thereon. Distortion of the wire conduit 24 would interfere with the advancement of the wire strand into its final proper position in the fastening forming mechanism.

For the purpose of the present invention there is provided on the hub 68 of the hand lever 66 a wire stopping member 80 (Fig. 4) which extends laterally from the hub 68 and which in one position of the hand lever 66, namely when the pressure roll 32 is in its inoperative position, is located in its operative position in the path of movement of the wire strand w, as illustrated in dot-and-dash lines in Fig. 1 and also as illustrated in full lines in Fig. 3. In addition to this position of the hand lever -66 and the already described position shown in full lines in Fig. 1 in which the flat portion of the hub 68 engages the abutment 12 and the pressure roll 32 is in its operative position, there is a third position of the hand lever 66 in which the hand lever points substantially upward. In the latter position of the hand lever 66 another portion of the round hub 68 is in engagement with the abutment 12 thus rendering the pressure roll 32 inoperative. Moreover, the wire stop 80 also is located in its inoperative position, that is, in a position in which it cannot act to stop the wire strand w. Obviously the wire stop 80 can be moved into its operative position only when there is no wire between the tworolls 30 and 32, for example, if the supply of wire has become exhausted. Before threading in a new wire strand through the wire guiding and feeding elements and into the fastening forming mechanism of the illustrated machine, the stop 80 is moved into its operative position (Fig. 3 and dot-and-dash lines in Fig. 1) by moving the hand lever 66 into a substantially horizontal position in which a round portion of its hub 68 engages the abutment l2 and forces the pressure roll 32 into its inoperative position. The operator of the illustrated machine now passes the leading end portion of the new wire strand to through the wire guide 14, thence between the rolls 30 and 32 and finally against the stop an. The operative position of the wire stop 8|] in the machine is critical in that the distance between this stop and the proper final position of the front end of the wire strand in the fastening forming mechanism, as measured along the path of movement of the wire strand into the fastening forming mechanism, is an integer multiple of one wire feed increment.

Inithepresent example this distance corresponds to six times a wire feed increment. With the newly presented Wire strand abutting the wire stop the operator now throws the hand lever 66 into thefull lineposition, shown in Fig. l, with theresult. that the wire stop 8B ,is moved out of its operative'position and the pressure roll 32 is moved into its operative position in which itclamps the front end portion of the wire strand against the feeding roll 35. By now running the machine idly through six cycles, six positive feeding movements are imparted to the wire strandlas indicated by the successive stages a to g in Fig. 1, with the result that the wire strand. isthreaded through the wire guiding and feeding elements into its proper final position in the fastening forming mechanism in which its front end is located at g and its leading end portion is in readiness to be severed by the knife I6 for the formation of a full size staple.

The distance a-g along the path of movement of the .wire: strand may be varied, if need be, by adjusting the wire straightener 26 heightwise of the machine.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a wire feeding mechanism, the combination with a wire feeding roll, a cooperating pressure roll bodily movable with relation to the feeding roll into and out of pressure applying position and a hand lever for controlling the bodily movement of the pressure roll, of a wire stop secured to the hand lever in such a position that it is moved into the path of movement of a wire strand when the hand lever is actuated to move the pressure roll out of pressure applying position.

2. In a wire feeding mechanism, the combination with a wire feeding roll, a cooperating pressure roll bodily movable with relation to the feeding roll into and out of pressure applying position, a hand lever for controlling the movement of the pressure roll and a hub on the hand lever mounted to rotate about the same axis as the pressure roll and provided with a flat and a round portion, of a wire stop secured to the hub, a fixed abutment cooperating with the hub to determine the position of the pressure roll with relation to the feeding roll, the arrangement being such that when the round portion of the hub contacts the abutment the pressure roll is located in its inoperative position and the wire stop is located in its operative position, whereas when the flat portion of the hub contacts the abutment, the pressure roll is in its pressure applying position and the stop in its inoperative position.

3. In a wire feeding mechanism, the combination with an intermittently rotated wire feeding roll adapted to impart uniform feeding increments to a wire strand, a cooperating pressure roll bodily movable with relation to the feeding roll into and out of pressure applying position, and a hand lever for controlling the bodily movement of the pressure roll, of a wire stop on the hand lever, the stop being arranged to be located in a wire stopping position when, to facilitate threading a new strand of wire into the wire feeding mechanism, the pressure roll is moved out of its pressure applying position, the arrangement being such that in the wire stopping position of the stop the distance, as measured along the path of movement of the wire, between the stop and the front end of the wire strand when in its proper final position, is a multiple of 4; feed increment, and means not-heather the pressure r011 has been restored to its ipresiure appiying position and the wire stop been moved out of wire stopping position or rotating the feeding roll a number of times corresponding to said multiple, so as to insure movement .of the wire strand into its proper final position.

4. In a wire feeding mechanism, the *combination with a wire feeding member, a cooperating presser member "movable with relation to the feeding member int-o and out pressure applying position, of a wire stop movabieinto and'out of a "wire stopping position, and a member for eontrolling both the 'pressermember and the wire stop, the controlling member indented to be located in different control positions, in one of which the presser member is loc'a'ted in "pressure applying position end the wire stop out of wire stop ing position, in another :of which the presser member is located out "of pressure app! 29 passer member and the wire stop are located in their inoperative positions.

5. In a wire feeding mechanism, a wire feed ingmember, a cooperating presser member movabie with relation to the feeding member into and outrof :pressm'e applying position, a normally inoperative wire stop, and manually eontmlied meansiz: which the stop is secured, said means being eontmllable for moving the presser memb'erzoutof andmto'pressure applying position and for simultaneously moving the wire stop into and out, :of operative position.

HERMAN A. JIM-HOE.

Number 1 Mackenzie i Oct. 24, 1922 

